Yesterday, a mother and daughter came to my consultation room. The mother is a senior editorial director of a television station, and the daughter is a freshman student who has just entered the university. The mother had an anxious and worried look on her face, and her speech was incoherent. Only after I comforted her, the mother and daughter slowly made their medical history clear. It turned out that the daughter returned home to Yan’an to visit relatives during the Spring Festival, just in time for the heavy snow and cooling, the third day of the new year with a cold and fever, sore throat, cough, temperature 39 ℃, dark tea-colored urine in the afternoon, rushed to the hospital for examination, found high blood, urine protein + + + +, urine occult blood + + + +, urine red blood cells full field of view, white blood cells 15-30 / high magnification field of view. He was given intravenous antibiotics, and his temperature went down the next day, and the hematuria disappeared. The routine urine test was negative for urine protein, but the red blood cells were still high. When her mother heard about the condition, she was uneasy and rushed to take her daughter back to Beijing. Li Jijun, Department of Nephrology, The First Affiliated Hospital of the General Hospital of the Chinese People’s Liberation Army Before coming to me, they had gone to 3 hospitals and the results of the routine urine examination were similar, but the doctor’s explanation did not relieve the mother’s anxiety, she always felt that there was no hope if she had kidney disease and that she would soon have kidney failure and uremia, so she could not feel at ease and could not eat or sleep well. I did not rush to explain the condition, but did further systematic examination. Blood pressure and blood picture were normal; urine routine: urine protein negative, occult blood ++, red blood cells 12-25/high magnification field, white blood cells negative; urine sediment bitewise examination of red blood cells was polymorphic; 24-hour urine protein quantification was negative; kidney function creatinine clearance 108 ml/min; pharyngeal swab culture did not find pathogenic bacteria; kidney ultrasound examination also did not find abnormalities. In fact, the daughter had a very common occult nephritis, clinically manifested as persistent microscopic hematuria with predominantly polymorphic red blood cells, no or only a small amount of urinary protein (1 g/24 hr urine), and normal renal function. In the acute phase, especially when the upper sensation or fever is present, it can be accompanied by episodes of carnitic hematuria, and when the body temperature is normalized, the carnitic hematuria can disappear quickly. If a renal puncture biopsy is done, the pathology is often IgA nephropathy, which is by far the most common primary glomerulonephritis, approaching half of the patients with renal biopsy. It can be divided into 7 types according to the different clinical manifestations, the most common being 3 types such as recurrent sarcoid hematuria, isolated sarcoid hematuria and asymptomatic abnormal urinalysis, which account for 70% of the number of patients with IgA nephropathy. Clinically, the disease is often stable, the pathological changes are relatively mild, the renal function is normal, and the prognosis is good. In contrast, the presence of hypertension and large amounts of proteinuria are often indications of a poor prognosis, and if the disease is not detected and treated in time, the disease will progress more rapidly and renal insufficiency will occur. Since that episode of carnituria, my daughter has only a small amount of microscopic hematuria, no hypertension, proteinuria, and normal kidney function, her condition should be relatively stable, and she can be treated without medication for the time being, and it does not affect her daily life and study. However, it is necessary to observe the changes of urinary routine regularly, which can be checked once in 1-2 months, especially when upper respiratory tract infection and fever occur, it is more important to check urinary routine at the same time. And at this stage, regular check-ups are more important than treatment. The purpose of checking creatinine clearance now is also to set a control background for future observation of dynamic changes in kidney function. In this case, renal puncture biopsy can also be suspended, because the pathological changes are often mild at this time, and the adjustment of treatment is not very useful, but if clinical symptoms such as urine protein, hypertension and renal function changes appear during the observation process, it is necessary to promptly clarify the cause, timely renal puncture biopsy and actively intervene in the treatment. If the microscopic hematuria is more, you can also intermittently take blood-activating drugs such as Bao Ren Kang. You should also pay attention to strengthen physical exercise, increase or decrease clothes in time when the weather changes, and try to reduce the number of colds. If there are frequent episodes of tonsillitis and recurrent carnitic hematuria or proteinuria, removal of the tonsils can be considered after controlling the inflammation, and the condition of some patients will be stabilized as a result. Although cryptogenic nephritis cannot be cured, but if you usually pay attention to observation and timely treatment, kidney function can remain stable for decades, and it is not that having nephritis is equal to uremia. The mother’s eyebrows were opened and a smile appeared on her face for the first time. Finally, there are two more points to remind you. First, most patients with chronic kidney disease can be completely asymptomatic or less symptomatic in the early stages, and many kidney disease patients are found during physical examinations or visits for other diseases, so it is important to take the initiative to check early. To adhere to regular annual urine screening, a routine urine test that is both simple and inexpensive can detect most kidney diseases. Secondly, renal function tests are equally important for patients who have been diagnosed with chronic kidney disease, or who have high risk factors such as hypertension and diabetes mellitus. And it is important to dynamically observe creatinine clearance (Ccr, normal value: 80-100 ml/min), which can reflect the degree of damage to glomerular filtration function earlier. In most adults, serum creatinine will only start to rise when Ccr drops by about 50%, and by then the kidney function has already been lost by half, and the best time for treatment of chronic kidney disease is also missed.